Consider casting to float32 by default in TableVectorizer

[GaelVaroquaux]

Problem Description

Using float64 instead of float32 typically incurs compute and memory loads, and users do not have this in mind.

Feature Description

We should add an option to the TableVectorizer to output float32. We should consider whether this is the default.

Alternative Solutions

N/A

Additional Context

N/A

[jeromedockes]

that also applies (maybe even more) to encoders, for example MinHash outputs float64

[GaelVaroquaux]

that also applies (maybe even more) to encoders, for example MinHash outputs float64

Absolutely! Thanks for raising this. Maybe we should start there

[TheooJ]

Closing because this has been addressed in the postprocessing step of the TableVectorizer in #902